Generally, dispensers, which discharge a predetermined amount of liquid- or gel-phase contents, such as a cosmetic, at one time using pneumatic pressure, are classified into a dip tube type dispenser, in which some of the contents is drawn into a dip tube and is discharged from casing while the same volume of air is drawn into the casing, and an airless type dispenser, in which a piston is moved upwards by vacuum pressure and contents are thus pushed upwards.
FIG. 1 shows an example of a conventional airless type dispenser. As shown in the drawing, the conventional airless type dispenser includes a container 2, which stores contents therein, a dispenser cap 10, which is coupled to the upper end of the container 2 and pumps the stored contents, and a button 20, which protrudes from the upper end of the dispenser cap 10 so as to be movable upwards and downwards. A nozzle 22, through which contents pumped by the button are discharged outside the container, is provided at a predetermined position in the button 20. The dispenser further includes an outer lid 6, which covers the button 20 and the dispenser cap 10.
Furthermore, a cylinder 12, which extends to the contents in the container 2, is provided in the dispenser cap 10. A hollow shaft 14 and an inner cap 16, which are coupled to a stem 24 provided on the lower end of the button 20, are open at first ends thereof, and have a through hole 13 at a predetermined position, are also provided in the dispenser cap 10. The hollow shaft 14 and an inner cap 16 are moved upwards and downwards in the cylinder 12 to create vacuum pressure for discharging contents, drawn into the cylinder 12, outside the container. As well, an inlet 12a, which is openably closed by a ball valve 18 made of metal, is formed in the lower end of the cylinder 12. A spring 19, which supports the hollow shaft 14 upwards, is interposed between the inlet 12a and the hollow shaft 14. In the drawing, the reference numeral 1 denotes a piston, which is provided in the container 2 and is moved upwards by vacuum pressure.
In the conventional dispenser having the above-mentioned construction, a user separates the outer lid 6 from the container 2 and thereafter pushes the button 20. Then, the piston 1 compresses the contents, thereby some of the contents is discharged from the container 2. Here, depending on the case, the amount of contents that is required may vary. However, in the case of this dispenser, when the button 20 is pushed, because the piston 1 moves a constant distance, the same amount of contents is always discharged, regardless of the amount of the contents that is required. Furthermore, it is very difficult for the user to control the distance that the button 20 is moved when pushing the button 20. As such, the conventional dispenser is problematic in that it is difficult to adjust the amount of contents that is discharged.